As a related technique for detecting a stripe pattern, there is disclosed in Patent Document 1, for example, a configuration for detecting a zebra zone, drawn on a road surface, from an image acquired by a camera mounted on a vehicle. FIG. 15 shows an example configuration of a stripe pattern detection system. This stripe pattern detection system includes an image input device 1510, a bird's-eye image forming means 1501, a template storage means 1502, a template read means 1503, a template matching means 1504 and stripe pattern detection means 1505. FIG. 15 is newly drawn for the present description as a new block diagram for illustrating the function of a back monitor computer of Patent Document 1. This stripe pattern detection system operates as follows:
The image input device 1510 inputs the image which is a subject of zebra zone detection acquired by a camera mounted on a vehicle.
The bird's-eye image forming means 1501 forms a bird's-eye image by converting the image acquired by the camera mounted on a vehicle so as to command a bird's-eye view of the road surface from a virtual viewing point located above the real world.
The template read means 1503 then reads a template of a zebra zone pattern that is estimated to exist in the vicinity of an own vehicle at a current time among templates representing patterns of zebra zones stored beforehand in the template storage means 1502.
The template matching means 1504 then matches the template of the zebra zone pattern to the bird's-eye image at each position within a certain range of the bird's-eye image.
In case the degree of coincidence between the template and the bird's-eye image is of a maximum value, and there is a location or locations where the degree of coincidence exceeds a preset threshold value, the stripe pattern detection means 1505 concludes that the zebra zone has been detected at the location of the bird's-eye image.
Such a template indicating a pattern specific to each zebra zone site present on a map is stored in the template storage means 1502 as a pre-stored template of a zebra zone pattern.
Patent Document 1:
    JP Patent Kokai Publication No. JP-P2007-153031A